Advanced Robust Control Design For High Speed Tilting Trains

<p>Tilting is a worldwide accepted technology concept in railway transportation. Theparticular benefit from tilting trains use is reduction in journey times due to speedincrease on track corners (while maintaining acceptable passenger comfort), a pointthat facilitates improved customer service. An additional benefit is cost effectivenessdue to the train running on existing rail tracks. Many countries opted to using tiltingtrains as means of fast public transportation (UK, USA, Canada, Sweden, Norway,Switzerland, Germany, Japan).The industrial norm of tilting high speed trains is that of precedence tilt wherebypreview tilt enabling signals are used to provide the required information to thevehicles (it can also use a combination of track database information or GPS but theconcept is the same). Precedence tilt tends to be complex (mainly due to the signalinterconnections between vehicles and the advanced signal processing required formonitoring). Research studies of earlier than precedence schemes,i.e. the so-callednulling-type schemes whereby local-per-vehicle signals are used to provide tilt (adisturbance rejection-scheme although tends to suffer from inherent delays in thecontrol feedback), are still an important research aim due to the simple natureand most importantly due to the more straightforward fault detection compared toprecedence. Use of nulling-type tilt has been supported by recent studies in thiscontext.The research presented in this thesis highly contributes to simplified single-inputsingle-output robust tilt control using the simplest rail vehicle tilt structure, i.e. anActive Anti-Roll Bar. Proposed are both robust conventional (integer-type) controlapproaches and non-conventional (non-integer) schemes with a rigorous investigation of the difficult to achieve deterministic/stochastic tilt trade-off. Optimizationhas been used extensively for the designs. A by-product of the work is the insightprovided into the relevant tilting train model Non Minimum Phase characteristicsand its link to uncertainty for control design. Work has been undertaken usingMatlab, including proper assessment of tilt ride quality considerations.</p>